Center bearing for hydraulic locomotives



Jan. 12, 1937. w. FERRls CENTER BEARING FOR HYDRAULIC LOCOMOTIVES 5 Sheets-Sheet 1 Original Filed Jan. 30, 1933 Sv j i: .w- N m bil n W \w kun o f l l ./N .a w I\ ra. A N z flllllll mm hm Jan. l2, 1937. w. FE'RRls vCENTER BEARING FOR HYDRAULIC LOCOMOTIVES Original Filed Jan. 30, 1933 5 Sheets-,Sheet 2 INVENTUR "3' WALTER FERFIS EY W TTRNEY.

Jan. 12, 1937; w. FL-:Rls

CENTER BEARING FOR HYDRAULIC IJOCDMOTIVEISl original Filed Jan. so, 1933 5 sheets-sheet s INvr-:NTDR WALTER F' E Films BY l @zw TTRNEY.

Jan. 12, 1937'. w. FERRls CENTER BEARING FOR HYDRAULIC LOCOMOTIVES Original Filed Jan. 30, 1933 5 Sheets-Sheet 4 INVENTCIR WALTER FERRIE- BY Jan. 12, 1937. w. FERRls 2,067,483

CENTER BEARING FOR HYDRAULIC LocoMoTIvEs Original Filed Jan. 30, 1933 5 Sheets-Sheet 5 U ql INVENTUH WALTER FEHHIS Patented Jan. 12, 1937 UNITED STATES PATENT OFFICE CENTER BEARING LOCOM FOR HYDRAULIC OTIVES Walter Ferris, Milwaukee, Wis., assignor to The Oilgear Company, Milwaukee, Wis., a corporation oi' Wisconsin 15 Claims.

This invention relates to self-propelled vehicles ofthe type having a body or frame supported upon a plurality of trucks, one or more iluid motors arranged upon one or more of the 6 trucks to drive the vehicle, and a power plant arranged upon the body or frame and connected to each motor to supply fluid thereto, such as the power vehicle described and claimed in Patent No. 2,037,373, issued April 14, 1936 'on applieation Serial No. 654,157 filed January 30,

1933 of which this application is a division.

In order that the vehicle may travel around curves, it is essential that each truck be permitted to turn relative to the body or frame and that each motor be connected to the power plant through a exible joint.

This invention has as an object to provide a vehicle of the above character with a center bearing which supports the body or frame upon a truck, permits the truck to turn relative to the body or frame, transmits propelling force from the truck to the body or frame, and provides means for transmitting motive iluid from the power plant to the motor or motors.

'Ihe invention is exemplined by the hydraulic locomotive shown somewhat schematically in the accompanying drawings in which the views are as follows:

Fig. 1 is a side elevation of the locomotive.

Fig. 2 -is a top plan view of one of the trucks.

Fig. 3 is a vertical section taken on the irregular line 3 3 of Fig. 2.

Fig. 4 is a horizontal section taken on the line d-d of Fig. 3.

Fig. 5 is a transverse section taken in the plane of the line 5 5 of Fig. 2.

Fig. 6 is a top plan View of the center bearing as indicated in Fig. 3 by the arrows 6-6.

I Fig. 7 is a sectional plan view taken along the 40 irregular line 'I-I of Fig. 3.

Fig. 8 is a detailed sectional view of a flexible joint through which liquid is transmitted from the power plant to the motors.

Fig. 9 is a diagram of the hydrauliccircuit.

The locomotive has not been fully illustrated nor will it be described in detail for the reason that it is illustrated and described in the application referred to above.

Briey, it is provided with a body I which is .y supported upon two trucks 2 and 2a and carries two internal combustion engines 3 and 3a and two reversible pumps 4 and 4 which are driven, respectively, by the engines 43 and 3B.

The trucks 2 and 2 are identical but are arranged in the reverse position in the body I.

That is, one truck is turned end for end in respect to the other truck.

'I'he locomotive is symmetrical about its transverse centerline and, in order that corresponding parts may be readily distinguished, the parts on 5 one side of the centerline have been designated by certain reference numerals and the corresponding parts on the other side of the centerline have been designated by the same reference numerals Vwith the exponent a `added.

The body I is supported upon each of the trucks by a center bearing consisting of a post 5 and a Asocket 6 winch willbe described in detail hereinafter.

Each truck is supported at one end by two l5 wheels fixed upon an axle I and at the other end by two wheels iixed upon an axle 8. As shown in Figs. 2 and 3, the axle 'I is driven by a variable displacement rotary hydraulic motor 9 through single reduction gearing IIl-I I, and the 20 axle 8 is driven by a variable displacement rotary hydraulic motor I2 through double reduction gearing I3--I4-I5.

Under certain conditions of operation, the motors 9 and I2 are simultaneously supplied 25 with liquid from the pumps 4 and 4a so that the torque of the two motors is .the same. Consequently, the motor I2 will operate at a higher speed than the motor 9 and will exert a greater rotative force upon the axle 8 than the motor 30 9 exerts upon the axle 'I due to the fact that the ratio of the gearing I3--Ifl-I5 is much greater than the ratio of the gearing IIl-I I.

The motors 9 and I2 are driven by liquid supplied thereto from the pumps 4 and 4a. The 35 direction in which the motors are driven depends upon the direction in which the liquid is delivered thereto, and the speed at which eachA motor is driven depends upon its displacement and upon the rate at which the liquid is de- 40 livered to the motor.

The displacement of the motor 9 is varied by a cam wheel I6 (Fig. 3) acting through a bell crank lever I1 which has one of its arms connected by a pin and slot connection to the stroke changing element of the motor and its other arm provided with a `roller and urged by a spring I8 in a direction to decrease motor displacement, the spring I8 holding the roller against the periphery of the cam wheelv I6.

Displacement of the motor I2 is varied by a cam wheel I9 acting through a bell crank lever 20 which has one of its arms connected by a pin and slot connection to the stroke changing element of the motorand its other arm pro- 55 vided with a roller and urged by a spring 2I in a direction to decrease motor displacement, the spring 2I holding the roller against the periphery of the cam wheel I9.

The cam wheels I6 and I9 may be rotated simultaneously by a Acontrol shaft 22 (Figs. 2 and 3) which is connected by suitable gearing to the shafts on which the cam wheels I6 and I9 :are xed. The shaft 22 is connected through suitable shafting and gearing to a handwheel 23 (Fig. l) arranged at one end of the body I, universal joints being arranged in the shafting to provide for the trucks pivoting beneath the body when the locomotive travels around a curve. 'I'he motors on the truck 2a are similarly controlled from the same handwheel so that all motors may be adjusted simultaneously.

TheV contours of the cam wheels I6 andi I9 are such that, during rotation of the handwheel 23, the displacement of the motor I2 is gradually reduced faster than the displacement oif the motor 9 until the displacement of motor I2 is at a predetermined minimum at which time it is suddenly reduced to zero and the motor short-circuited, and the displacement of the motor 9 is simultaneously suddenly increased by a like amount as fully explained in the application re'- ferred to above. Thereafter, the displacement of the motor 9 may be gradually reduced until it isi.

at a predetermined The delivery of liquid to the motors is controlled by varying the rate and the direction of delivery from the pumps 4' and 4a each of which has it displacement varying mechanism connected luy-suitable linkage to a lever 24 arranged at one end of the body I.

When the lever 24 is in its central or neutral position, the pumps are at zero stroke and no liquid is being delivered thereby. When the lever 24 is moved in one direction or the other from neutral position, the pumps will deliver liquid in one direction or the other and at a rate depending upon the distance the lever 24 is moved from its neutral position.

In starting the locomotive from a stationary position, at which time the pumps 4 and 4B :are at zero stroke, the control wheel 23 is operated to adjust Ythe motors to full stroke in order that they may have the highest torque and then the control lever 24 is operated to adjust the pumps and cause them to deliver liquid at a limi-ted volumetric rate to the motors whereby the full power of the engines 3 and 3e is available for operating the motors at slow speed and enabling them to exert high rotative forces upon the driving wheels and thereby,l start the locomotive and its load. I

After the locomotive has been started, the control lever 24 may be operated to increase pump displacement and thereby increase the speed of the locomotive untilthe pumps are at full stroke and then the handwheel 23 may be operated to reduce motor displacement and thereby further increase the motor speed with the resultant increase in the speed of the locomotive.

When the handwheel 23 has been rotated until the displacement of the high speed motor I2 has been reduced to the predetermined minimum, the motor I2 is operating at approximately the highest speed for which it is designed to work with its pistons reciprocating and transmitting power. Further rotation of the handwheel 23 causes the 'high speed motor on each truck to be suddenly adjusted to zero displacement and short-circuited and the entire output` of the pump to be directed the high speed motors.

to the two low speed motors the displacementsof which were suddenly increased simultaneously with the sudden reduction in the displacement of the handwheel 23 reduces the displacement of the two low speed motors and further increases the speed of the locomotive.

The characteristics thus far described form no part of the present invention but are described and claimed in the application referred to above.

When the motors are energized to propel the locomotiveLthe inertia of the body I and the draw-bar force exerted by the locomotive tend to shift weight from the leading axle of each truck to the following axle of that truck in respect to the direction of movement for the reason that the draw-bar pull and thel center of gravity of the accelerated masses are in much higher planes than the rails which exert tractive force upon the wheels. The amount of weight thus shifted is proportional to the tractive force exerted by the locomotive, and the tractive foce is proportional to the working pressure existing in the liquid which drives the motors.

If no provision were made for counteracting this weight-shifting effect, the front wheels of each truck would slip long before the motors exerted a maximum rotative force upon the rear wheels, thereby materially limiting the tractive eiort of the locomotive.

Slippage of the front wheels of a truck is prevented by exerting an independent loading force upon the front axle of the truck in response to a tractive effort of the locomotive or by so supporting the locomotive upon the truck that the.l

front axle of the truck carries a. greater weight than the rear axle when -the locomotive is idle. In the latter case, when the locomotive Stillfurther rotation of v is started or is exerting a tractive effort upon an weight shifted from the frontaxle to the rear axle will approximately equalize the load upon the two axles at the maximum draw-bar pull and enable both the front and the rear wheels to have suflicient traction to start the locomotivev or to move an independently supported load.

If unequal loading of the axles were solely depended upon to prevent wheel slippage, it is, obvious that all of the wheels would have suflicient traction only when the locomotive was operated in but one direction, while `if the application of an independent loading force to the front axles were solely depended upon to prevent wheel slippage, it would be necessary to provide mechanisms forselectively exerting independent loading forces upon all. axles in order that the locomotive might operate in either direction and all of its wheels have sumcient traction in either direction of operation.

In order that the number of mechanisms for exerting independent loading forces upon the axles may be kept at a minimum in a locomotive' which is operable in either direction, the locomotive body is supported upon each truck ata point nearer to one axle than to the other axle so that independently supported load, the- 2 is arranged nearer the axle 1 than to the axle 75 3, a hydraulic jack 25 is secured to the body I above the axle 8 to exert an independent loading force thereon whenever the locomotive tends to move in the direction which makes the axle 8 the leading axle.` The truck 2a is turned end for end so that the two axles 'I and 'IP carry greater loads than the center axles 8 and 8 when the locomotive is idle, and a hydraulic jack 25B is secured to the body I above the axle 8a to exert an independent loading force thereon whenever the locomotive tends to move in the direction which makes the axle 8 the leading axle of truck 2B.

Of course, the arrangement could be reversed so that the center bearings would be arranged nearer the center axles 8 and 8a and the jacks 25 and 25u would be arranged above the axles l and 1B.

The jack 25 consists primarily of .a cylinder 26 and a piston 2'I `fitted therein and provided upon its lower end with a roller 28 to engage a bearing plate 29 xed between two beams 30 which extend across the end of the truck 2 and are supported upon the side frames thereof.

The cylinder 26 is fastenedto the body I upon the under side thereof as by being secured between two channel bars l3| which extend across the body I and are fastened to the side sills thereof. The jack 25B is similarly constructed and arranged.

As shown in Fig. 9, the cylinder 26 of the jack 25 is connected at its upper end by a pipe 32 to a pipe 33 intermediate the ends thereof. The pipe 33 has one of its ends connected to the socket 6 of the center bearing on the truck 2 and its other end connected to a pipe 34 intermediate the ends thereof. The pipe 34 has its ends connected to corresponding ports of the pumps 4 and 4a and is connected intermediate its ends by a pipe 33a to the socket Iia of the center bearing on the truck 2a.

The cylinder 2lia of the jack 25a is connected at its upper end by a pipe 32a to a pipe 35a intermediate the ends thereof. The pipe 35 has one of its ends connected to the socket 6 of the center bearing on the trucks 2u and its other end connected to a pipe 36 intermediate the ends thereof. The pipe 36 has its ends connected .to corresponding ports of the pumps 4 and 4e and is connected intermediate its ends by a pipe 35 to the socket 6 of the center bearing on the truck 2. V

The arrangement is such that, when the pumps 4 and 4 deliver liquid into'the pipe 34, the motors will move the locomotive toward the right in respect to Fig. l and the pressure in the cylinder 26 will be proportional to the tractive effort of the locomotive, thereby enabling the jack 25 to exert a loadilforce upon the axle 8 to overcome the weight shifting eil'ect of the tractive force. When the pumps 4 and 4a deliver liquid into the pipe' 36, the motors will move the locomotive in the opposite direction and the jack 25*a will be 'energized to overcome the weight shifting effect of the tractive force.

The above described mechanism for exerting independent loading forces upon the axles 8 and 8a forms no part ofthe present invention but is described and claimed in Patent No. 2,042,519.

As previously stated, the present invention' relates more particularly to the center bearings which support the bodyv I and transmit propelling forces thereto and through which liquid is delivered by the pump to the motors and returned from the motors to the pump.

The center bearing on the truck 2 has its male part or bearing post 5 rigidly secured in a casing 40 which encloses the driving mechanism and is xed to the side frames of the truck by the plurality of webs 4I (Figs. l2 and 5). The post 5 has its lower end reduced in diameter and fitted in a socket 42 which is supported from the side walls of the casing 40 by webs 43. The socket 42 supports the post. 5 andrestrains the lower end thereof from movement in any direction.

The post 5 is provided upon its upper end with a spherical head 44 and has its upper end restrained frommovement in any lateral direction by a thrust block 45 which is closely tted upon the post 5 below the head 44 and rigidly fastened between two strutsv 48 extending across the top of the casing 40 and secured to the side walls thereof. The socket 42 and the thrust block 45 enable the post 5 to transmit propelling forces from the truck 2 to the body I.

Weight is transferred from the body I to the post 5 through the socket 6 which is rigidly secured to the body I upon the underside thereof as by means of four varms 41 secured to or formed integral with the socket Gand fastened to the under frame of the body.

'Ihe spherical head 44 on the post 5 extends upward into a bore which is formed in the socket 8 and is cylindrical from the bottom of the socket 6 to substantially the horizontal centerline of the head 44, lthen changes to spherical form and conforms to the surface of the head 44 for a short distance, and then opens into a recess 48 formed in the socket 6.

The recess 48 contains a bearing plate 49 which bears against the top of the recess but is free to shift laterally as the truck shifts slightly relatively to the socket 6. Bearing plate 49 has a concave underface complementary to the head 44 and bearing thereon to transfer weight from the body I to the head 44.

The bearing plate 49 has oil grooves formed in its underface and is provided with lubricant through a channel not shown.

The post 5 has two uid channels 50 and two fluid channels 5I extending axially thereof and then radially outward and terminating upon the spherical surface of the head 44 which preferably has a segment of its upper part made as a separate piece which forms a bearing cap 44 and rests upon the flat horizontal top of the head proper.

The cap 44 provides a smooth and uniform bearing surface upon the top of the head 44 after the channels 50 and 5I have been drilled from the outside of the head and the upper ends of the axial parts of the channels plugged, as shown in Figs. 2 and 5.

'Ihe channels 50 are formed diametrically opposite each other in the post 5 and connected together at the lower ends thereof as shown in Fig. 5. The lower ends of both channels 50 are connected by a pipe 52 (Figs. 3 and 9) to the motor 9 and by a pipe 53 to a valve 54 which controls the motor I2 and is adapted to short-circuit it when motor displacement has been reduced to a predetermined minimum, as explained in U. S. Patent 2,037,373 referred to above. V

'I'he channels 5I are arranged diametrically opposite each other from the channels 50 and have the lower ends thereof connected together. The lower ends of both channels 5I are connected to the motor 9 by a pipe 55 and to the valve 54 by a pipe 56 as shown in Figs. 3 and 9.

The channels 50 and 5I communicate, respec- 75 tively, with the pipes 33 and 35 each of which is divided at its lower end (Fig. 1) into two branches and connected tothe socket 6 by a tting 51 (Figs. 5 and '7) one of which is arranged upon each of the four sides of the socket. The pipe 33 has its two branches connected to the fittings 51 upon opposite sides of the socket 6 and the pipe 35 has its two branches connected to the fittings 51 which are on the other two sides of the'socket 5 and consequently opposite each other.

Each tting 51 is rigidly secured to the socket 6 and forms an oil-tight joint therewith. As best shown in Figs. 5 and 7, each fitting 51 is fastened to the socket 5 by bolts 58 and has a cylindrical inner end tightly fitted in a bore 59 (Fig. 8) which is formed in the socket 6 and extends from 'the outside thereof to the bore in' which the head 44 of the post 5 is arranged.

Each fitting 51 has a bore 60" formed in the lower part thereof and communicating at its outer end with a branch of the pipe 33 or the pipe 35. The bore 60 has a hollow plunger or thimble 6I closely fitted therein and urged againstl the head 44 by a spring 62 arranged in the outer end of the bore 60.

The inner end of the thimble 6I is closely fitted to' the surface of the head 44 and has a drainage or pressure limit groove 63 formed therein between its inner and outer peripheries.

The liquid in the outer end of the bore 66 acts upon the outer end of the thimble 6I 'and urges the inner end thereof againstl the head 44 with a force proportional to the pressure of the liquid. The thimble 6I is thus urged against the head 44 by the constant force exerted by the spring and by a" variable force exerted by the liquid. 'Ihe with suflicient force to prevent unnecessary leak- V age between the thimble and the head. The groove 63 is drained, as by means of one or more small grooves extending therefrom to the outer periphery of the thimble, so that the pressure therein and between the bearing surfaces outside of said groove is substantially zero.

The bore of the thimble 6I and the upper end .,of the channel 56 or 5I .with which it registers are so projmtioned that they will remain in registry when the truck pivots beneath the body l as the locomotive travels around the sharpest curve which may be encountered.

Due to the fact that the pipes 33 and 35 are connected to the socket 6 at points diametrically opposite each other, the socket 6 is hydrostatically balanced upon the head 44, thereby permitting the head 44 to turn easily in the socket 6 and permitting substantially duid-tight joints between the head 44 and the socket 6 to be easily provided.

The head 44 and the socket 6 provide a universal joint for supporting the body I and, together with the thimbles 6 I, provide fiexible fluid connections between the pumps on the body and the motors on the trucks. Further, the arrangement is such that the trucks may be removed by simply elevating the body I without disconnecting any pipe or mechanical connection.

Liquid employed for lubricating the head 44 and any liquid escaping past the thimble 6| is collected upon an annular collector plate 54 which is closely fitted upon the post 5 below the head 44 and has its outer periphery fitted within an annular flange depending from and carried by the socket 5.

Suitable packing is employed to prevent leakage from the chamber which is formed by the plate 64 and the, flange 65 -from which liquidfis drained into the casing 40 through a channel not shown. The plate 64 is urged downward against the thrust block 45 by a plurality of springs 66 which may also be employed to retain the packing in position. Y(

'Ihe center bearing on the truck 2 corresponds exactly to the center bearing on the truck 2. Consequently, such parts as are shown have been indicated by corresponding reference numerals 'with the exponent "a added. However, since the truck 2 is reversed in respect to the truck 2, the fluid connections between the trucks and the body are also4 reversed in order that the motors on both trucks may operate in the same direction. That is, the channels 50 in the post 5 are connected through the pipe 35 to the pipe 36 and the channels 5In are connected through the pipe 33a to the pipe 34.

The invention herein set forth is susceptible of various modifications without departing from the scope thereof as hereafter claimed.

The invention is hereby claimed as follows:

l. In a power vehicle having a body, a truck arranged beneath said body, a hydraulic motor carried by said truck to propel said vehicle and a pump carried by said body for supplying motive liquid to said motor, the combination of an upper bearing member fixed to said body and having uid channels connected to said pump, and a lower bearing member fixed to said truck and fitted to said upper bearing member to support said body and having uid channels connected to said motor and in registry with. the fluid channels in said upper bearing member, said bearing members forming a universal joint between said body and said truck and forming flexible fluid connections between said motor and said pump.

2. In a power vehicle having a body, a truck arranged beneath said body, a hydraulic motor carried by said truck to propel said vehicle and a pump carried by said body for supplying motive liquid to said motor, the combination of an upper bearing member fixed to said body and having fluid channels connected to said pump, and a lower bearing member fixed to said truck and fitted to said upper bearing member to support said body and having uid channels connected to said motor and in registry with the fiuidchannels in said upper bearingl member, said bearing members forming a universal joint between said body and said truck and forming flexible uid connections between said motor and said pump and said fluid channels being so arranged that said bearing members are hydrostatically balanced in respect to each other.

3. In a. power vehicle having a body, a source of motive fluid carried by said body, a truck arranged beneath said body to support at least a part of the weight thereof, and iiuid operated driving means arranged upon said truck to drive said vehicle, the combination of a casing secured to said truck and enclosing said driving means,

ing to support said body upon said truck and to provide a pivoted driving connection between said body and said truck, said center bearing having fluid channels extending therethrough for the passage of motive fluid to and from said driving means and fluid-tight joints between the upper and lower parts thereof and said fluid channels being arranged in pairs with the channels of each pair connected together and arranged diametrically opposite each other to hydraulically balance said upper part upon said lower part.

4. In a power vehicle having a body, a truck arranged beneath said body to support at least a part of the weight thereof, a fluid motor carried by said truck for propelling said vehicle,

andaK source of motive fluid carried by said body, the combination of a female bearing secured to said body and having a substantially semi-spherical socketand fluid channels leading outward from said socket and connected to said motive fluid source, a malebearing secured to said truck and having a substantially spherical head fitted in said socket to support said body and to enable said truck to impart motion thereto, said male bearing having fluid channels formed therein in communication with the fluid channels in said female bearing, and means connecting said motor to the fluid channels in said male bearing. I

5. In a power vehicle having a body, a truck arranged beneath said body to support at least a part of the weight thereof,'a fluid motor carried by said truck for propelling said vehicle, and a source of motive fluid carried by said body, the combination of a female bearing secured to said body and having a substantially semi-spherical socket and fluid channels leading outward from said socket and connected to said motive fluid source, a male bearing secured to said truck and having a substantially spherical head iltted in said socket to support said body and-'to enable said truck to impart motion thereto, said male bearing `having fluid channels formed therein in communication with the fluid channels in said female bearing, means connecting said motor to the fluid channels in said male bearing, and a hollow plunger arranged in each of said female bearing channels to be urged by the fluid pressure in that channel against the surface of said head to thereby provide a Huid-tight joint between said bearings.

6. In a power vehicle having a body, a truck arranged beneath said body to support at least a part of the weight thereof, a fluid motor carried by said truck for propelling said vehicle, and a source of motive fluid carried by said body, the combination of a female bearing secured to said body and havinga substantially semi-spherical socket and four fluid channels leading outward from said socket and connected to said motive fluid source, a male bearing secured to said truck and having a substantially spherical head tted insaid socket to support said body and to enable said truck to impart motion thereto, said male bearing having fluid channels formed therein in communication with the fluid channels in said female bearing, two of the channels in each of said bearings being diametrically opposed to each other and connected together and the other two channels in each of said bearings being Connected t each other and spaced 90 from the ilrst two channels whereby said female bearing is pressure balanced upon said male bearing, and means connecting said motor to the fluid channels in said male bearing.

7. In a power vehicle having a body, a truck arranged beneath said body to support at least a part of the weight thereof, a fluid motor carried by said truck for propelling said vehicle,

and a source of motive fluid carried by said body, the combination of a female bearing secured to said body and having a substantially semi-spherical socket and four fluid channels leading o'utward from said socket and connected 'to said motive iluidsource, a male bearing selin each of said bearings being connected to each other and spaced 90 from the first two channels whereby said female bearing is pressure balanced upon said male bearing, means connecting said motor to the fluid channels in said male bearing, and a hollow plunger arranged in each of said female bearing channels to be urged by the fluid pressure in that channel against the surface of said head to thereby provide a fluid-tight joint between said bearings.

8. In a power vehicle having a body, a source of motive fluid carried by said body, a truck arranged beneath said body to support at least a part of the weight thereof, and fluid operated driving means arranged upon said truck to propel said vehicle, the combination of a vertical vcenter bearing post rigidly secured to said truck fixed to said body and having a socket complementary to said head and fitting upon and around said head and forming with said male bearing a center bearing to transfer weight from said body to said head and to enable said truck to transmit motion to said body, said female bearing having fluid channels formed therein with each in registry with one of the fluid channels in said male bearing and forming therewith a continuous passage through said center bearing, means connecting the upper ends of said passages to said source, and means connecting the lower ends of said passages to said 'driving means.

9. In a power vehicle having a body, a source of motive fluid carried by said body, a truck arranged beneath said body to support at least a part of the weight thereof, and fluid operated driving means arranged upon said truck to proy having fluid channels formed therein and extending upward through said post into said head and'then laterally outward to terminate upon the surface of said head, a female bearing fixed to said body and having a socket complementary to said head and fitting upon and around said head and forming with said male bearing a center bearing to transfer weight from said body to said head and to enable said truck to transmit motion to said body, said female bearing having fluid channels formed therein with each in registry with one of the -fluid channels in said male bearing and forming therewith a continuous passage through said center bearing, a hollow plunger fitted in each of said female bearing channels and urged against said head by the fluid pressure in that channel to form a duid-tight joint between said female bearing and said male bearing, means connecting the upper ends of said passages to said source, and" means connecting the -l'ower ends of said passages to said driving means.

10. In a power vehicle having a body, a source of motive fluid carried by said body, a truck arranged beneath said body to support at least a part of the weight thereof, and fluid operated driving means arranged upon said truck to propel said vehicle, the combination of a Vertical center bearing post rigidly secured to said truck fixed to said body and having a socket complel mentary to said head and fitting upon and around said head and forming with said male bearing a :center bearing to transfer weight from said body to said head and to enable said truck to transmit motion to said body, said female bearing having four fluid channelsformed therein with each in registry with one of the uid channels in said male bearing and forming therewith a continuous passage through said center bearing, means connecting the upper ends of .said passages to said source, and means connecting the lower ends of said passages to said driving means; two of said passages being connected together and arranged diametrically opposite each other and the other two passages being connected to each other and-arranged 90 from the ilrst two passages whereby said female bearing is pressure balanced uponv said head.

11. In a power vehicle having a body, a source of motive uid carried by said body, a truck arranged beneath said body to support at least a part of ,the weight thereof, and fluid operated driving means arranged uponsaid truck to pro-` pel said vehicle, the combination of a vertical center bearing post rigidly secured to said truck at the top and the bottom thereof, a spherical head xed to said post upon the upper end thereof and forming therewith a male bearing having four fluid channels formed therein and extending upward through said post into said head and then Alaterally outward to terminate upon the surface of said head, a female bearing fixed to said body and having a socket complementary to said head and fitting upon and around said head and forming with said male bearing a center bearing to transfer weight from said body to said head and to enable said truck to transmit motion to said body, said female bearing having four fluid channels formed therein with each in registry with one of the fluid `channels in said male bearing and forming therewith` a continuous passage through said center bearing, a hollow plunger tted in each of said female bearing channelLand urged against said head by the fluid pressure in that channel to form a fluid-tight joint between said female bearing and said male bearing, means connecting the upper ends of said passages to said source, and means connecting the lower ends of said passages to said driving means; two of said passages being connected together and arranged diametrically opposite each other and the other two passages being connected to each other and arranged 90 from the first two passages whereby said female bearing is pressure balanced upon said head. l

12. In a power vehicle having a body, a source of motive fluid carried by said body, a truck arranged beneath said body to support at least a part of the weight thereof, and fluid-operated driving means arranged upon said truck to propel said vehicle, the combination of a casing enclosing said driving means and secured to said truck, a vertical center bearing post rigidly secured to said casing at the top and the bottom thereof, a spherical head fixed to said post upon the upper end thereof and forming therewith a male bearing having fluid channels formed therein and extending upward through said post into said head and then laterally outward to terminate upon the surface of said head, a female bearing fixed to said body and having a socket complementary to said head and fitting uponand around said head and forming 4with said male bearing a center bearing to transfer weight from said body to said head and to enable said truck to transmit motion to said body, said female bearing having fluid channels formed therein with each in registry-with one of the fluid channels in said male bearing and forming therewith a continuous passage through said center bearing, means connecting the upper ends of said passages to said source, and means connecting the lower ends of said passages to said driving means.

13. In a power vehicle having a body, a source of motive uid carried by said body, a truck arranged beneath said body to support at least a part of the weight thereof, and fluid operated driving means arranged upon said truck to propel said vehicle, the combination of a casing enclosing said driving means and secured to said truck, a vertical center bearing post rigidly secured to said casing at the top and the bottom thereof, a spherical head fixed to said post upon the upper end thereof and forming therewith a male bearing having fluid channels formed therein and extending upwardthrough said post into said head and then laterally outward to terminate upon the surface of said head, a female bearing fixed to said body and having a socket complementary to said head and fitting upon and around said head and forming with said male bearing a center bearing to transfer weight from said body to said head and to enable said truck to transmit motion to said body, said female bearing having fluid channels formed therein with each in registry with one of the fluid channels in said male bearing and forming therewith a continuous passage through said center bearing, a hollow plunger fitted in each of said female bearing channels and urged against said head by the fluid pressure in that channel to form a fluid-tight joint between said female bearing and said male bearing, means connecting the upper ends of said passages to said source, and means connecting the lower` ends of said passages to said driving means.V

14. In a power vehicle having a body, a source of motive fluid carried by said body, a truck arranged beneath said body to support at least a part of the weight thereof, and uid operated driving means arranged upon said truck to propel said vehicle, the combination of a casing enclosing said driving means and secured to said truck, a vertical center bearing post rigidly secured to said casing at the top and the bottom thereof, a spherical head xed to said post upon the upper end thereof and forming therewith a male bearing having four fluid channels formed therein and extending upward through said post into said head and then laterally outward to terminate upon the surface of said head, a female bearing xed to said body and having a socket complementary to said head and fitting upon andaround said head and forming with saidmale bearing a center bear-` ing to transfer weight from said` body to said head and to enable said truck to transmit motion to said body, said female bearing having four fluid channels formed therein with each in registry with one of the fluid channels in said male bearing and forming' therewith a continuous passage through said center bearing, means connecting the upper ends of`said passages to said source, and means connecting the lower ends of said passages to said driving means; two of said passages being connected together and arranged diametrically opposite each other and the other two passages being connected to eachother and arranged 90 from the first two passages whereby said female bearing is pressure balanced upon said head.

15. In a power vehicle having a body, a source 40 of motive fluid carried by said bodya truck arranged beneath said body to support at least a part of the weight thereof, and fluid operated .driving means arranged upon said truck to propel said vehicle, the combination of a casing enclosing said driving means and secured to said truck, a vertical center bearing post rigidly secured to said casing at the top and the bottom thereof, a spherical head fixed to said post upon the upper end thereof and forming therewith a male bearing having four uid channels formed therein and extending upward through said post into said head and then laterally outward to terminate upon the surface of said head, a female bearing fixed to said body and having a socket complementary to said head and fitting upon and around said head and forming with said male bearing a center bearing to transfer weight from said body to said head and to enable said truck to transmit mo tion to said body, said female bearing having four uid channels formed therein with each in registry with one ofthe fluid channels in said male bearing and forming therewith a continuous passage through said center bearing, la hollow plunger tted in each of said female bearing channels and urged against said head by the uid pressure in that channel to form a fluid-tight joint between said female bearing and said male bearing, means connecting the upper ends of said vpassages to said source, andmeans connecting the lower endsof said pasf sages to said driving means; two of said passages being connected together and arranged diametrically opposite each other and the other two passages being connected to each other and arranged 90 from the rst two passages whereby said female bearing is pressure balanced upon said head.

WALTER FERRIS. 

